Water footprint and virtual water flows from the Global South: Foundations for sustainable agriculture in periods of drought.

Freshwater availability has decreased alarmingly worldwide, with agriculture playing a vital role in this trend. The assessment of the agricultural water footprint (WF) and virtual water flows (VWF) is fundamental not only in local water resources management and protection, but also in our understanding of the synergies between local water consumption and global markets. Thus, the WF - broken down into its components (blue, green, and gray) - of the leading 21 crops (grouped in fruit, legumes, cereals, and vegetables), grown in four basins with the most significant agricultural activity in central Chile was determined, estimated in two consecutive years 2017-2018. In addition, due to their great importance in exports, VWFs were assessed, establishing connections according to their origins and destinations. The results show that the green and gray water footprints increased significantly in the south-central basins, while blue water consumption increased in the basins of the central zone, reflecting an evident WF transition in accord with latitude and climate conditions. Furthermore, VWF showed an annual increase of 44 %, in about 116 destinations, with Asia, Europe, and North America being the preferred destinations, with annual variations of VWF associated with increases in exports of apples, cherries, grapes, blueberries, and walnuts, market preferences and growing areas. The present study is an initial step toward sustainable agriculture in a commodity exporting country, one that is relevant in the exploitation of virtual water yet faces severe water deficit problems, distribution, and local water policies. Therefore, contributing to encouraging the efficiency and value of water in the process of a new institutional framework.